summaryrefslogtreecommitdiffstats
path: root/arch/microblaze/lib/uaccess_old.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/microblaze/lib/uaccess_old.S')
-rw-r--r--arch/microblaze/lib/uaccess_old.S176
1 files changed, 176 insertions, 0 deletions
diff --git a/arch/microblaze/lib/uaccess_old.S b/arch/microblaze/lib/uaccess_old.S
new file mode 100644
index 0000000000..dd5f3bfbc2
--- /dev/null
+++ b/arch/microblaze/lib/uaccess_old.S
@@ -0,0 +1,176 @@
+/*
+ * Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2009 PetaLogix
+ * Copyright (C) 2007 LynuxWorks, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <asm/page.h>
+
+/* Loop unrolling for __copy_tofrom_user */
+#define COPY(offset) \
+1: lwi r4 , r6, 0x0000 + offset; \
+2: lwi r19, r6, 0x0004 + offset; \
+3: lwi r20, r6, 0x0008 + offset; \
+4: lwi r21, r6, 0x000C + offset; \
+5: lwi r22, r6, 0x0010 + offset; \
+6: lwi r23, r6, 0x0014 + offset; \
+7: lwi r24, r6, 0x0018 + offset; \
+8: lwi r25, r6, 0x001C + offset; \
+9: swi r4 , r5, 0x0000 + offset; \
+10: swi r19, r5, 0x0004 + offset; \
+11: swi r20, r5, 0x0008 + offset; \
+12: swi r21, r5, 0x000C + offset; \
+13: swi r22, r5, 0x0010 + offset; \
+14: swi r23, r5, 0x0014 + offset; \
+15: swi r24, r5, 0x0018 + offset; \
+16: swi r25, r5, 0x001C + offset; \
+ .section __ex_table,"a"; \
+ .word 1b, 33f; \
+ .word 2b, 33f; \
+ .word 3b, 33f; \
+ .word 4b, 33f; \
+ .word 5b, 33f; \
+ .word 6b, 33f; \
+ .word 7b, 33f; \
+ .word 8b, 33f; \
+ .word 9b, 33f; \
+ .word 10b, 33f; \
+ .word 11b, 33f; \
+ .word 12b, 33f; \
+ .word 13b, 33f; \
+ .word 14b, 33f; \
+ .word 15b, 33f; \
+ .word 16b, 33f; \
+ .text
+
+#define COPY_80(offset) \
+ COPY(0x00 + offset);\
+ COPY(0x20 + offset);\
+ COPY(0x40 + offset);\
+ COPY(0x60 + offset);
+
+/*
+ * int __copy_tofrom_user(char *to, char *from, int len)
+ * Return:
+ * 0 on success
+ * number of not copied bytes on error
+ */
+ .text
+.globl __copy_tofrom_user;
+.type __copy_tofrom_user, @function
+.align 4;
+__copy_tofrom_user:
+ /*
+ * r5 - to
+ * r6 - from
+ * r7, r3 - count
+ * r4 - tempval
+ */
+ beqid r7, 0f /* zero size is not likely */
+ or r3, r5, r6 /* find if is any to/from unaligned */
+ or r3, r3, r7 /* find if count is unaligned */
+ andi r3, r3, 0x3 /* mask last 3 bits */
+ bneid r3, bu1 /* if r3 is not zero then byte copying */
+ or r3, r0, r0
+
+ rsubi r3, r7, PAGE_SIZE /* detect PAGE_SIZE */
+ beqid r3, page;
+ or r3, r0, r0
+
+w1: lw r4, r6, r3 /* at least one 4 byte copy */
+w2: sw r4, r5, r3
+ addik r7, r7, -4
+ bneid r7, w1
+ addik r3, r3, 4
+ addik r3, r7, 0
+ rtsd r15, 8
+ nop
+
+ .section __ex_table,"a"
+ .word w1, 0f;
+ .word w2, 0f;
+ .text
+
+.align 4 /* Alignment is important to keep icache happy */
+page: /* Create room on stack and save registers for storing values */
+ addik r1, r1, -40
+ swi r5, r1, 0
+ swi r6, r1, 4
+ swi r7, r1, 8
+ swi r19, r1, 12
+ swi r20, r1, 16
+ swi r21, r1, 20
+ swi r22, r1, 24
+ swi r23, r1, 28
+ swi r24, r1, 32
+ swi r25, r1, 36
+loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */
+ /* Loop unrolling to get performance boost */
+ COPY_80(0x000);
+ COPY_80(0x080);
+ COPY_80(0x100);
+ COPY_80(0x180);
+ /* copy loop */
+ addik r6, r6, 0x200
+ addik r7, r7, -0x200
+ bneid r7, loop
+ addik r5, r5, 0x200
+
+ /* Restore register content */
+ lwi r5, r1, 0
+ lwi r6, r1, 4
+ lwi r7, r1, 8
+ lwi r19, r1, 12
+ lwi r20, r1, 16
+ lwi r21, r1, 20
+ lwi r22, r1, 24
+ lwi r23, r1, 28
+ lwi r24, r1, 32
+ lwi r25, r1, 36
+ addik r1, r1, 40
+ /* return back */
+ addik r3, r0, 0
+ rtsd r15, 8
+ nop
+
+/* Fault case - return temp count */
+33:
+ addik r3, r7, 0
+ /* Restore register content */
+ lwi r5, r1, 0
+ lwi r6, r1, 4
+ lwi r7, r1, 8
+ lwi r19, r1, 12
+ lwi r20, r1, 16
+ lwi r21, r1, 20
+ lwi r22, r1, 24
+ lwi r23, r1, 28
+ lwi r24, r1, 32
+ lwi r25, r1, 36
+ addik r1, r1, 40
+ /* return back */
+ rtsd r15, 8
+ nop
+
+.align 4 /* Alignment is important to keep icache happy */
+bu1: lbu r4,r6,r3
+bu2: sb r4,r5,r3
+ addik r7,r7,-1
+ bneid r7,bu1
+ addik r3,r3,1 /* delay slot */
+0:
+ addik r3,r7,0
+ rtsd r15,8
+ nop
+ .size __copy_tofrom_user, . - __copy_tofrom_user
+
+ .section __ex_table,"a"
+ .word bu1, 0b;
+ .word bu2, 0b;
+ .text